(a) Field of the Invention
This invention provides an annular-arranged lamp capable of backward projecting by concave sphere, in which two or more than two light emitting devices (110) arranged in a circular or polygonal means being annularly installed at the side of annular heat dissipation device to be installed with light emitting devices (102) of the lamp, and the light projecting axial line of each light emitting device (110) is projected towards a reflection device with concave sphere (103) disposed above the annular heat dissipation device (101), light beams of the light emitting devices (110) are reflected by the reflection device with concave sphere (103) then refracted to a preset projection range, thereby forming a unified light source.
(b) Description of the Prior Art
When a conventional lamp is configured by multiple light sources, there is a shortage of illumination deterioration due to uneven brightness formed at different locations. Such shortage shall be improved.